Processing of sulfur-vulcanizable materials and related compositions and articles



Patented Sept. 14, 1954 PROCESSING OF SULFUR-VULCANIZABLE MATERIALS AND RELATED COMPOSI- TIONS AND ARTICLES John C. Hillyer, Bartlesville, and Daniel A. Nicewander, Eli; City, Okla., assignors to Phillips Petroleum Company, a corporation of Delaware No Drawing. Application April 6, 1951,

Serial No. 219,770

26 Claims.

This invention relates to plasticizers and ex-' tenders and their utilization in processing sulfurvulcanizable organic plastic substances containing unsaturated carbon-to-carbon bonds, and to compositions associated with such processing. In one embodiment this invention relates to a method for plasticizing natural and synthetic rubbers. In another embodiment this invention relates to new compositions comprising natural and synthetic rubbers each incorporated with a polycyclic aldehyde produced by the interreaction of a butadiene and a furfural. This application is a continuation-in-part of our copending application, Serial No. 81,413, filed March 14, 1949.

Rubber stocks are tough and nonplastic and must be softened or rendered in a plastic condition to readily absorb ingredients incorporated therewith in the processing of these materials. Exemplary of such ingredients are suitable reinforcing pigments such as carbon black, fillers such as zinc oxide, various accelerators, sulfur and the like which are among those which in various combinations impart improvements to the final vulcanizate, with respect to such characteristics as for example, abrasion, flex life, hysteresis, resistance to tear, tensile strength, elongation, modulus, and the like.

Mixing of tough rubber stocks with compounding ingredients is effected generally by means of mastication or softening, i. e., plasticization, at a controlled temperature in the range of 50-350" F. Mastication involves mechanically kneading the rubber material, either by passing it through an open mill, i. e., passing it between rollers running at different speeds whereby it is subjected to compression followed by a shearing action, or by placing it in an enclosed mixer of the Banbury type where much the same effect is produced. The open mill and the Banbury type mixer comprise standard equipment in compounding rubber. Various known agents are used to accelerate milling by virtue of their affinity for the rubber or rubber-like material and are referred to hereinafter as plasticizers or softeners, i. e., as applied to synthetic, natural, and reclaimed rubber.

Various types of materials have been employed as softeners or plasticizers for both natural and synthetic rubbers and His known that variations in properties of rubber products can be produced through the use of different plasticizing agents. A good plasticizer, in addition to softening a rubber stock, must give a finished product with other desirable properties. Some materials which exert the desired plasticizing action often have deleterious eifects on other prop erties to the extent that the finished product, i. e., the vulcanizate, is of little value for many purposes. One of the disadvantages of some synthetic elastomers is that they do not possess sufficient tack. A plasticizer which gives a product of improved tack as well as other good physical properties is highly desirable.

We have now discovered novel softeners and extenders, which by their incorporation with rubber stocks, are good rubber plasticizers and tackifiers and also impart other desirable properties to the rubber. These materials are applicable in compounding natural and synthetic rubbers and reclaimed rubber, and they can be used alone as softeners and tackifiers in a compounding recipe or as mixtures with each other, or in conjunction with other softeners. They are effective not only as plasticizers and tackifiers but the rubber in which they are used shows particularly good flex life and tensile strength.

An object of this invention is to provide new and novel plasticizers and extenders for utilization with natural and synthetic rubbers. Another object is to provide a method for plasticizing and extending sulfur-vulcanizable organic plastic substances containing unsaturated carbonto-ca'rbon bonds. Another object is to provide new compositions each comprising a sulfur-vulcanizable organic plastic substance containing unsaturated carbon-to-carbon bonds, incorporated with an aldehydic polymer produced by the interreaction of a butadiene or a selected homologue thereof, with a furfural or a selected homologue thereof. Another object is to provide selected vulcanizates as new compositions. Another object is to provide improved softeners which impart desirable swelling and extractability characteristics to Perbunan rubbers. Other objects will be apparent to one skilled in the art from the accompanying discussion and disclosure.

The term sulfur-vulcanizable organic plastic substance containing unsaturated carbon-to- 7 carbon bonds herein is meant to be generic to natural rubber, synthetic rubber, and reclaimed rubber.

In accordance with our invention we have 7 provided a method for plasticizing and extending sulfur-vulcanizable organic plastic substances containing unsaturated carbon-to-carbon bonds, and new compositions comprising such organic plastic substances incorporated with an aldehydic polymer produced by the interreaction of a butadiene with a furfural. We have discovered that natural rubber, and sulfur-vulcanizable synthetic rubber-like materials or rubber substitutes, i. e., synthetic rubbers, as for example butadient-styrene copolymer, Perbunan, Butyl rubber, neoprene and the like, and reclaimed rubber, can be plasticized and extended by the incorporation therewith of an aldehydic polymer of the type described, which functions also as an extender therefor.

' As we have disclosed in our earlier filed copending application referred to, a diolefin such as 1,3-butadiene and its immediate homologues may be reacted with a furfural such as furfural and its immediate homologues, to produce new products including aldehydic polymers which have a polycyclic structure. Since these polycyclic products are generally produced in a mixture also containing polymers of butadiene, polymers of furfural, and other complex materials of a polymeric nature, and since their chemical identities were originally unknown, the term polymers and copolymers have been loose- 1y applied to these polycyclic chemical compounds as well as to these other polymeric materials. In view of the identification of certain of these materials as definite compounds, as discussed herein, the use of the term polymers tends to be misleading and the products are more accurately defined as polycyclic reaction products. When reacting 1,3-butadiene with furfural, one of the major reaction products is a pale yellow or amber colored oil. The crude oil apparently is a somewhat complex mixture of various reaction products. It has a boiling range of from about 200 F. to about 320 F. under a pressure of about one millimeter of mercur absolute. The refractive index at 77 F. ranges from about 1.520 to about 1.530 and the specific "gravityat 68 F. ranges from about 1.08 to 1.16. The average molecular weight is about 210. The physical properties of various fractions of the oil vary somewhat within the indicated boiling range; The average refractive index at 77 F. is about 1.526 while the average specific gravity at 68 F. is about 1.12.

. In the fractional distillation of the oil so produced, various fractions may be obtained as products of theprocess. The physical properties of of the products may thus be varied somewhat 'by separating the oil into fractions having various boiling point ranges. For example, fractions of different viscosity may be obtained by fractional distillation to produce on the one hand an oil of low viscosity and on the other, an oil of high viscosity or one having a slurry-like consistency. The aldehydic content is variable depending on conditions used, in general the content is between 40 and 80 mol per cent,'but under suitable operatingconditions almost any .value can be obtained. We have found, for instance, that the product distilling near the upper end of the boiling range is generally very low in aldehyde content. By pehtane extraction of .a lower boiling fractionon the other hand, a

4 product of very high aldehydic content is obtained.

As a diolefin reactant in the preparation of the aldehydic polymer plasticizer-extender of our invention we prefer to use a conjugated diolefin, preferably one having. not more than about seven carbon atoms per molecule. Such a diolefin can be referred to as a member of the group consisting of 1,3-butadiene and its immediate homologues and may be reported as having the formula V R! R! R! R! Hei hts where each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms and at least two R. 's are hydrogen. The furfural reactant employed can be referred to as one of the group consisting of furfural and its immediate homologues having not more than seven carbon atoms per molecule. Such a material may be said to be a compound having the formula Where each R is of the group consisting of hydrogen and methyl and at least one R is hydrogen. The more commonly used reactants are 1,3-butadien and furfural, isoprene and furfural, and. piperylene and furfural, and the corresponding diolefins with methyl furfural. It appears that in producing such an aldehyde reaction product, two molecules of the diolefins react with one molecule of the furfural reactant by a modification of the Diels-Alder reaction.

The aldehyde reaction products include compounds having the empirical formula where a: is an integer not greater than 2 and y is an integer not greater than 4. These aldehydes probably have the following structural formula Where each R is of the group consisting of hydro"- gen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the R'm and in the R'n in each case, not greater than three and at least two of the R'm and of the R'n are hydrogen.

A preferred mode of operation of our invention' may be illustrated with a reaction system comprising furfural of approximately five per cent water content by weight and butadiene in concentrations from three to fifty percent by weight. The system is charged to an autoclave and maintained at temperatures within the range of from about 200 F. to about 300 F. for from about 5 to about hours. The reaction product is then removed, unchanged reactants stripped off, and the higher boiling portion fractionated under reduced pressure. Butadiene dimer, Which may also be formed in an appre ciabie amount when temperature and hutadierie concentrations are suflicientiy hi h, distiils at 97 F. under an absolute pressure or 23 mm". of

mercury and is removed in the stripping pros essl The aldehydic' polymeric plasticiz'er ex tender materials of our invention are contained in the fraction distilling fromabout 150 F. to about 320 under an absolute pressure of about one mm. of mercury, which corresponds to about 450 to about 700 F; when converted to boiling temperatures at 760' mm, of mercury absolute. The major fraction of this material distills over head between 190 and 275 F5, under one mm. of mercury pressure.

The water content of the f urfural used in some commercial extractive distillation units, such as those operating on butylenc-butadiene separation, is usually about five weight per cent. Although, anhydrous furfural may be successfully employed to produce the polycyclic aldehyde, the presence of water in furiural, par ticularly at a concentration near this value; is not detrimental to the operation of this embodiment of our invention; In fact, water appears to have some catalytic effect on the reaction of butadiene with furfural to produce our plasticher-extender materials, and also enters into the reaction to produce a lactone. However, water present in the furfural in a concentration as ceeding to 20 per cent often accelerates a secondary condensation to form undesirable tarry substances which contaminate the aldehydic product, thus reducing its yield; High temperatures above about 390 F. may also accelerate such secondary condensations as already described and should be avoided. Temperature be low 160 F; usually requires substantially extended time. s

The polycyclic aldehydicplasticizer-extender material of this invention can be obtained as a by-product of an extractive distillation process involving the use of furtural as a selective sol vent in the separation of butadiene from a butadiene-butene hydrocarbon mixture undergoing fractional distillation in a distillation column. In such a process the butadiene-butene' stream is contacted with furfural generally containing from 4 to 6 Weight per cent water. Tem= peratures in various parts of the extractive distillation system range up to about 325 E, and the total contact time of butadiene, water, and furfural in the extractive distillation column is sufficiently long to provide for some appreciable side reaction, or condensation, of furfural with butadiene to form our polycyclic aldehydes, or of furfural with water and butadiene With the concomitant formation of some lactone by-prodnot. The magnitude of such extractive distillation operations is such that large volumes 'of furfural are in constant circulation in the system, and thus even a low conversion of furfural provides large amounts of the aldehydic product.

In the separation of butadihe from a butene stream in accordance with the extractive distillation procedure above referred to, it is generally customary to divert a small proportion, usually about 1 or 2 per cent of the circulating furfural stream, to a furfural rerun system, generally a steam or vacuum redistillation system,- for the purpose of removing by product furfural polymers. In such a rerun system, the furfuralbutadiene reaction product is separated from the furfu'ral, as a part of a tarry bottoms product,

containing large amounts of resinous iurfural polymer and the above mentioned lactone product, Separation of the aidehydic polycyclic compound from the tar can be effected by means or vacuum distillation generally at about 1 mm. absolute pressure or less. However if desired the total tarry residue can be employed. without further purification as a plasticizer-extender in accordance with our invention. In fact, the polycyclic aldehy'dic product can be utiiized in that capacity, in any state of purity desired.

Steam distillation when used in the removal of tar from the furfural side stream provides large amounts of water condensate which col.- lect with the bottoms product. The aqueous phase thus formed carries in solution a large proportion of the polycyclic aldehyde and also the lactone by-product, each of which can be separated by further distillation.

It is a feature of our invention that it is uiinecessary to utilize the polycyclic aldehyde formed during the extractive distillation described in a high state of urity, thus eliminating the cost of a final purification that would otherwise be required. We have found that we can use a crude polycyclic aldehyde contaiiiing' fraction recovered as a product of condensation of two mols of butadiene with one mol of iuriurai conducted under conditions already discussed herein, or effected as aside reaction in an extractive distillation method of the type already discussed; This, feature is particularly advantageous when utilizing the by-product material obtained from the furfural purification step already described. The tarry phase, from the extractive distillation process as described, when distilled under reduced pressure yields the polycyclic aldehydic product material together with some of the lactone, and these products can be readily separated to isolate the aldehyde in any desired purity, However since the lactone te'r'ials so formed and present in the total byproduct fraction do not adversely affect the function of the polycyclic aldehyde as a plasticizerextender it is advantageous from an economic standpoint to permit their presence and to thereby eliminate purification costs.

Recovery of the polycyclic aldehyde-containing fraction from the steam condensate, when steam distillation is employed in the furfural rerun step, may be effected by evaporation of the water, and the residual product utilized as a plasticizer extender in accordance with our invention. However when desired the residual product from such steam condensate distillation may be further treated, for example by means of solvent extraction, with a suitable selective solvent to remove the polycyclic aldehyde material in any desired degree of purity.

The preferred species of our extender-plasticizer material represented by the structural formula and is referred to as 2,3,4,5-bis(M-butenylene)- tetrahydrofuriural which species is produced by 7 the interreaction of furfuraldehyde with 1,3- butadiene and is that formed during the specific extractive distillation process described hereinabove.

The proportions of the plasticizer-extender 8 or vulcanized for a period of time in the range of from 20 to 75 minutes. In the accompanying claims, reference to a vulcanizate or product of vulcanization of a rubber or rubber-like material compound with a softener material of my invenparticularly those comprising organic solvents, gasoline-like materials or jet fuels, exhibit particularly high swelling and low extractability characteristics.

Rubber or rubber-like materials containing the materials employed with respect to the rubber tion means that the vulcanization occurred after stock in accordance with our invention vary, admixture of these materials with each other. depending upon the type rubber being proc- The following examples serve to further illusessedjand the properties desired in the finished trate our process for plasticizing natural and product, i. e., the plasticizer-rubber product pre- 10 synthetic rubber, and new and novel plast1c1zerceding or subsequent to vulcanization or both as containin composltlons formed 1n accordance desired. Generally the .amount of plasticizer- With our invention, by whichwe mean to inextender employed is within the limits of from elude those new compositions in their form be- 1 to 50 parts by weight per 100 parts by weight fore vulcanization and also after vulcanization. of rubber stock. When plasticizing relatively he rea a d the proportions d t high Mooney synthetic elastomers, for example other specific ingredients employed, as illustrated those having raw Mooney values of 90 or above in the p s, are pr s nt d as b in typl al as for example as high as 160 (ML-4), it is and should not be construed to limit the invenusually advantageous'to employ relatively large tion unduly. 'quantities of plasticizer, for example from 15 Example I to 50 parts by weight per 100 parts by weight of t 7 rubber. When plasticizing relatively low Mooney Freshly steam distilled furfural containing five synthetic elastomers, i. e., those having a raw P c t by Weight Water W charged 0 a Mooney value below 90 as from about 20 to 90, steel reaction vessel. Sufficient 1,3-butadiene that amount is in the range of from about 1 to was added to give a butadiene concentration of 25 parts, often from 2 to 10 parts. When re- 4.0 per cent in the reaction mixture. The comferring herein to Mooney value, it is meant that p on O t Charge material wa Mooney viscosity as determined in accordance with the AS'IM method, 13927-491. Furfuml Parts by g We can incorporate the softeners of our in- "f f vention with the material to be plasticized by any water suitable method, such as (1) adding the softener either directly or as a dispersion to a synthetic The temperature within the reaction vessel was rubber latex and then coagulating the latex in maintained at 260 F. for '70 hours. The reaction accordance with latex masterbatch procedure, product was then transferred to a specially deor (2) introducing the softener on the mill. signed distilling flask and stripped of water and Our invention is well applied to plasticization unreacted furfural andbutadiene under an absoor Perbunan rubbers prepared by copolymerizing lute pressure of from two to five mm. of mercury. acrylonitrile and 1,3-butadiene in a range of A residue containing some furfural and the furratios of 10:90 to 40:60 parts by weight. By in- 40 fural-butadiene condensation products was transcorporating the softener materials of our invenferred to a flask bearing a Vigreaux column and tion with a Perbunan rubber and vulcanizing the fractionated at pressure in the range 0.5-0.2 mm. mixture, we are able to prepare rubber vulcaniof mercury. The data observed during this diszates, which when contacted with hydrocarbons, tillation are tabulated as follows:

K 111 o H o 1 a 1 3 53 R r 1' e e P n OITGCG Isle S.G. t eracive Gut No. Tgnl p ii i Tgnfi p Te F- 3 a lig exoat cc. gms.

In the above distillation, fraction 1 comprises recovered furfural. Fraction 2 represents the transition between furfural and the light reaction product and is a mixture of the two. Fraction 3 was an amber colored liquid and is typical i softeners of 'our invention are preferably cured. 75 of the light reaction product or'polymer. The

first few milliliters of this fraction were slightly low-boiling and were probably contaminated with a little furfural. Fraction 4 can be regarded as the heart-cut of the light reaction product. Fraction is similar to fraction 4. Fraction 6 comprised the so-called heavy polymer product. 1 It consisted of a mixture of white crystals and a red viscous liquid. About 65 per cent of the total liquid product was the amber colored liquid designated as "light reaction product. Further investigation and identification {not specifically described herein) of the light reaction product thus formed showed the light product material to comprise a polycyclic aldehyde formed by the interreaction of two mols of butadiene with one mol of furfural and to have the empirical formula C13H16O2 and the structure,

furfural oi more than about 80 per cent. pu ty obtained by the interaction of two mols 1,3- butadiene with one mol furfural and characterized by a boiling point of 239 F. 1.1 mm. meroury absolute, a specific gravity /20 of 1.120, and a refractive index 20/D of 1.5240.

(2) A polymeric residue obtained from a furfural side stream drawn from an extractive distillation system employing furfural as a selective solvent in the recovery of 1,3-butadiene from a C4 hydrocarbon mixture. This polymeric residue was a brownish-black tarry residue substantially insoluble in Water (about 5 per cent being dissolved on prolonged contact with water), and contained about 10 per cent water (occluded) and less than 1 per cent unreacted furfural; it had a density of 1.20 grams'per cc., an acid number of 15 (mg. KOH/gram sample), and a bromine number, in C614, of 122.3. This polymeric residue contained about 15 per cent 2,3,4,5-biS(A butenylene) -tetrahydrofurfural.

(3) TB-90B, a well known liquid polyether of high molecular weight generally employed in low temperature plasticization, as a control, or reference for evalution of plasticizer materials (1) and (2) described immediately hereinabove.

(4) Dibutyl phthalate, as a control or reference for evaluation of plasticizer materials (1) and (2) described immediately hereinabove.

The following compounding recipe was employed:

Parts by w i ht 1 Medium abrasion furnace black. 3 Benzothiazyl disulfide.

Fraction 3 Fraction 4 Specific Gravity 1.10 at 77 F 1.13 at 68 F. Rel'ractive'Index, at 68 R... 1.5254 1.5265. Molecular Wei ht 210 208. Aldehyde Content 99.0 percent 83.5 percent. Acidity 0.82 percent (calculated as furoicacid);

Example II The following :materials were evaluated as rubber plasticizers and extenders in a 74/26 buta- The compounded stocks were each cured at 307 for minutes. The following .evaluae tier-1 d ta were obt ined:

200 F., Percent Gehman Plasticizer No. l 300 Tensile, Compression Freeze Percent Tensile, Percent p. s. i. 1 Set a "Point, -0. Modulus, p. s. i. Elongation p. s. i. a a

2, 260 2, 550 340 1, 390 8. 9 -.33..9 2, 270 2, 630 345 1, 270 7. 1 26. 7 1, 590 2, s40 44o 15. 0 5 an 380 y 2, 560 460 1s. 0 s7 OVEN AGED 24 HOURS AT 212 F e As identified immediately hereinabove. .45.minu te cures on aged stress-strain values.

diene-acrylonltrile copolymer prepared by emulsion polymerization:

(1) A condensation product fraction compris- Variable quantities of the 2,3,4,5bis(A -butening 2,3,4,5 bis(A butenylene) tetrahydroylene)-tetrahydrofurfura1, described in Example i1 as plasticizer (1) evaluated in a 74/26 butadiene-acrylonitrile copolymer which was prepared by emulsion polymerization. The high molecular weight polyether, designated as TP-90B was used as a control. The compounding recipe and procedure were the same as that of Example 30 minutes at 307 F. and physical'propertie's oi. each vulcanizate'determined. A control was run using a blend of equal parts of Paraflux (an as phaltic flux) with Circosol-ZXH (a p troleum 11 drocarbon softener containing hydrocarbons of high molecular weight in'the form of a heavy, viscous, transparent, pale green, odorless liquid 11. The following evaluation data were ob- 1O tained: of low volatility; sp. gr. 0.940 Saybolt viscosity 200 F. 1 Percent Gehmen Softener PHR 1 300 Percent v Tensile, Compression fi gfi Freeze odulus Tensile, Percent p. s. i. Set Point, C. S L p. s. i. Elongation 2,3,4,5-- bis (A buteny-.

lene)-tetrahydrofurfural 10 1, 490 2, 240 410 1, 020 13. 8 43 -37 2,3,4,5 bis (A butenylene)-tetrahydrofuriural 30 360 860 605 320 23. 8 21. -32. 5 TP90B 10 2, 2 50 2, 390 315 1, 020 14. 3 39. 5 -43 OVEN AGED 24 HOURS AT 212 F.

2,3,4,'5 bis (A butenylene)-tetrahydrofurfural 10 2, 380 2, 880 345 2,3,4,5 bis (A butenylene)-tetrahydrofurlural 1, 460 2, 180 445 P-QOB 10 2, 940 225 1 Parts per 100 parts rubber (by weight). B 45 minute cure.

Example IV 2,3,4,5 -bis(A -butenylene) tetrahydrofurfural (described in Example 11 as plasticizer (1), and a crude reaction product containing this compound and described in Example II as plasticizer (2) were evaluated as plasticizers in a tread recipe using a 41 F., 60 Mooney (ML-4)., 71/29 butadiene-styrene elastomer. Stocks were compounded using the following recipe:

Parts by weight Butadiene-styrene rubber 100 Philblack O 50 Softener 1 High abrasion furnace black.

2 A physical mixture containing 65 per cent of a complex diarylamine ketone reaction product and per cent of N,N'-diphenyl-p-phenylenediamine.

3 N-cyclohexyl-z-benzothiazolesulfenamide.

. The compounded stocks were milled and cured at 100 F., about 2000 seconds). The following evaluation data were obtained:

Plasticizer Cimosob Parafiux (1) (2) Blend Unaged Samples:

stressi strain properties at v I 300 Percent Modulus,

e p. s.i 780 940 l, 170 Tensile, p. s. i 3, 100 3, 280 3, 560 Elongation, Percent 715 710 610 Stress-strain properties at 20 F., 45 min. cures,

Tensile, p. s. i 2, 050 2, 330 2, 020 Hysteresis, A '1 F 92. 6 96. 0 66. 9 Resilience, Percent" 58.0 55. 6 61. 5 Flex e, M 24. 9 58 81. 5 Shore hardness 53 59 54 Compression set, Percent. 20. l 14. 4 17. 9 compounded MS 1% 36 46 37.5 Extrusion at 250 F.-

Inches/minutc..- 42. 2 36 40. 1 Grams/minute 103 Meter tack, separation load,

115 2!) 35 Oven Aged 24 Hours at 212 F..

Stress-strain properties at .80".F,.- 300 Percent Modulus,

.p. s. i l, 900 1, 620 2,

. Tensile, p. s. 3, 620 3, 480 3, 530

Elongation, Percent. 490 545 425 Hysteresis, A T F; 67. 9 76. 3 53. 0 Resilience, Percent" 63. 2 60. 4 67. 7 Flex life, M 12. 3 23. 8 l0. 7 Shore hardness 62 65. 5 60 Example V Butadiene-styrene rubber The crude reaction product containing 2,3,4,5-.- Philblack 50 bisiA -butenylene)-tetrahydrofurfural, designatr Z1110 93 V ed as plasticiaer (2 in Example III, was evalugfgggig f 1 619. in a i a es h recipe of $111611 j' ::':i ample IV. Three controls were run: (1) a blend santoeure 1 of equal parts of Circosol-ZXH with Parafiux; cnv ntional softener 10 (2) Paraflux; and (3) Asphalt (an aspha1t 1,0 B1fi5katd 1ene/furiural condensation prod.-. 135 type softener). The following evaluation data T;; ;'I';"g

are. ux, ircoso 5 or 311 alt were obtamed. *3 Softener 2 as in Example 1.1.

80 F. Extrusion at 200F P t 611 8 o 250 F. 300 Flex Hand P1ast1c1zer PHR? Tenslle, AT F. Res1l1- Hardpresounded K223i Tensila figg f p. s. i. I 61106 ness sign 15 5 Ta-ck lus, gation Set Min. M111. p. s.i

10 1,000 3,210 680 2,250 94.8 55.5 43.5 61 14.3 51 35 94 6 2... 3,050 735 2,020 100.6 53.7 55 61 12.6 39.2 96.1 6 Circosol-Paraflux 10 1.140 3.400 630 2,110 71.6 60.9 24.4 18.6 42 36 97.8 3 Paraflux 10 1,110 3,570 645 2,310 72.6 59.9 40.0 56 18.4 42 38.5 100 3 QVEN 151G111) 24 HOURS AT 212 F.

10 1,730 3.520 535 76.3 57.6 19.1 2 15 1,430 3,220 605 83.8 56.9 43.5 01150501.- 10 1,980 3,510 460 57.1 64.2 10.5 Paraflux. 10 2 040 730 495 58.5 65.1 15.3 115 511515116 10 2,030 3,430 455 61.2 62.7 4.8

1 Plasticizer (2) of Example II.

2 Parts per 100 parts rubber by we1ght,

3 45 minute cures.

4 Percent broken at 50,000 fiexures.

Emample VI The stocks were milled and cured 30 minutes The crude reaction product containing 2,3,4,5- at 307 F. The following evaluation data were bis(A, butenylene) tetrahydrofurfural, desigobtained;

F. Exgggglg n at Permnf 300 per 9 Percent Flex Shore 6.0m Plasticizer P113 v 41 F. RQSill- L116; Hardipresl 6 3 Tensile g g ence M 11088 $1011 g i In I G o uongap.s.. 4 .9 -m. 1118, S tlon 1115. p. s. 1

OVEN AGED 24 5101138 AT 212 11 D0 3 1,510 3,400 67. 61.5 10.6 62 O 5 1,280 3,330 73.6 59.7 15. 2 C1rcoso12XH l 2, 030 3, 780 59.-9 65. 8 8. 0 60. 6

Do 5 1,400 3, 20 71.9 58.6 17.7 63 Paraflux 2, 050 3. 730 02. 8 63. 9 8.1 62, 5

CIICOSOI2XH" 2, 290 3, 500 54. 7 66. 7 11'. 4 62 Asphalt #6 2, 230. 3, 650 62. 2 64. o 4 6 l 45 minute cures. V

1 Parts per parts by elghtoi the crude 2,3,4,5-bis (A butenylene)tetrahydrofurfural (plasti clzer-No. 2 of Erample II). nated as plasticizer (2) in Example II was evaluated in 555165 "quantities in conjunction with P51511551, Cirdosol-ZXH, and Asphalt #6. Evaluation of these plasticizer mixtures was made in 5115 tread recipe using 41 F. butadiene-styrene rubber of Example IV. Stocks were compounded 7 using the following recipe:

70 Example VII 2,3,4,5 l0i s (A buteny1ene) tetrahydrofurfural and a crude reaction product containing this compound. (both materials as described in Example II and designated respectively as plasticizers (1') and (-2)) were evaluated alone and in 15 mixtures with Staybelite Resin (hydrogenated rosin) as plasticizers in a carcass recipe using a 41 F., 60 Mooney (MLA) 71/29 butadiene-styrene elastomer. A control was run using a mixin the R'm and in the Rn' in each case, not greater than three and at least two of the R'm and of the R'n are hydrogen.

2. As a new composition a rubbery sulfur-vulcanizable organic plastic substance containing ture of Paraflux with Staybelite Resin. Stocks V were compounded in accordance with the followunsaturated carbon-to-carbon bonds, incorpoing recipe: rated with an aldehyde characterized by the Parts by weight structural formula Butadiene-styrene rubber 100 H H Philblack O 25 Zinc oxide 3 R R r l/ stearlc 301d V V 1 R c 0 C R/ 1 H II I Agerite Resm D V l C l Sulfur 2.5 Santocure 1 V R 0 11-32 0.2 1k E Softener 7.5

Polymerized trimethyldihydroquinoline. 7 1 {eaction product or butyraldehyde and butylidene where each R, is of the group cons1sting of hydro- 7 2o gen and methyl and at least one is hydrogen, and The stocks were milled and cured minutes each R is of the group consisting of hydrogen at 307 F. Thefollowing evaluation data Were and an alkyl group having not more than three obtained: carbon atoms with the sum of the carbon atoms 0 F. cement Flex Oom- Shore Hand Plasticlzer 300 Tensile AT 1 Res1l1- Life ounded Percent Tensile, gffgf p. s.i. ence M Hardness MS, 1% Tack Modulus, p. s. i g

p. s. i.

Plasticizer (1) of Example II 800 3,260 605 870 40. 9 73.0 7. 2 49 31. 5 6 Plasticizer 2) of Example II 640 3,690 700 1,120 46.3 71.4 16.6 51 32.5 7 Percent Plasticizer (l)+25 Percent Staybelite Resin 800 3, 760 630- 1,070 43. 3 74. 0 9. 2 50. 5 30. 5 6 75 Percent Plasticizer (2)+25 Percent Staybelite Resin 700 3,750 680 1,010 45.6 72.1 14.7 53 32.0 7 75 Percent Paraflux+25 Percent Percent Staybelite Resin 870 2,790 650 850 37.1 74.1 6.9 52 31.5 7

1 7 than three and at least two of the R'm and of the Rn are hydrogen.

5. As a new composition lo'fl p'arts by weight of a rubbery copolymer of a conjugated diene and a different unsaturated organic compound copolymerizable therewith compounded with 1 to 50 parts by weight of a plasticizer material comprising 2,3,4,5-bis(zi -butenylene) -tetrahydrofurfural.

6. A composition of claim 5 wherein said plasticizer material is a tarry residual by-product containing said tetrah'ydrofurfu'ral and is recovered from fur'fural previously utilized as a selective solvent in the extractive distillation of 1,3- b'u'tadiene from an; hydrocarbon mixture.

'7. A composition of claim 5 wherein s'aid'plasti'cize'r material is recovered from a steam condensate formed during steam distillation of furf'u'ral previously utilized as a selective solvent. in the extractive. distillation of Ls-butadiene from a C4 hydrocarbon mixture; 7

8. As a new composition 100" parts by weight of a rubbery buta'd'iene styrene copolymer compounded with from 1 to 50 parts by weight of 2,3,4,5-b'is (A -butenylene) -tetrahydrofurfuial.

9. As a new composition 100' parts by weight of a rubbery butadiene-acrylonitrile copolymer compounded with from 1 to 50 parts by weight of 2,3,4,5-bis (A -butenylene) -tetrahydrofurfural.

10. The product of vulcanization of 100 parts by weight of a rubbery sdlfuf-vulcanizable organic plastic substance containing unsaturated carbon-to-carbon bonds which has been vulcanized with sulfur in the presence of from 1 to 50 parts by weight of an aldehyde characterized by the structural. formula where each R is of the group consisting of hydrogen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the R'm and in the R'n in each case, not greater than three and at least two of the Rm and of the Rn are hydrogen.

11. The product of vulcanization of 100 parts by weight of a sulfur-vulcanizable synthetic rubher-like material which has been vulcanized with sulfur in the presence of 1 to 50 parts by weight of an aldehyde characterized by the structural formula where each R is of the group consisting of hydrogen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the Rm and in the R'n in each case, not greater T18 thanithree and at least two cfthe R'm and of the R11 are hydrogen.

12. A vulcanizate of claim 11 wherein said synthetic rubber-like material is a rubbery copolymerof a conjugated diene and an unsaturated organic compound copolymerizable therewith.

13. The product of vulcanization of 190 parts by weight of a suifur vulcanizable synthetic rubber lik'e material which has been vulcanized with sulfur in the presence of a product fraction formed during the liquid phase condensation of two mols of 1,3-butadiene with one mol of -fur iural at a temperature within the range of 200- 325 F. for a period of from 5-100 hours and containing 2,3,4,5-bis(A =butenylene) -tetrahydrofurfural. v

14. A vulcanizate or claim 13 wherein said syn"- thetic rubber-like material is a copolymer of butadiene and styrene.

15. A vulcanizate of claim 13 wherein said synthetic rubber-like material is a copolymer of butadiene and acrylon itrile.

16. The product of vulcanization of 100 parts by weight of a rubbery butadiene-styrene copolymer vulcanized with sulfur in the presence of from 1 to 50 parts by weight of 2,3,4=',5-bis(A -butenylene) -tetrahyd'rofurfural.

17. The product of vulcanization of 100 parts by weight of a rubbery butadiene-acryldnitrile copolymer vulcanized with sulfur in the presence of from 1 to 50' parts by weight of 2,3,4,5-bis(A butenylene) -tetrahydrofurfura1. I

18. A produce of vulcanization of 100 parts by weight ofa rubberybutadiene styrene copolymer. vulcanized with sulfur in the presence of from 1 to 50 parts by weight of a tarry residual by-prod'uct containing 2,3,4,5-bis(A -butenylene) -tetrahydrofurfural and recovered from furfural previously utilized as a selective solvent in the extractive distillation of 1,3-butadiene from a C4 hydrocarbon mixture. V r 19;; A vulcanizate of claim 18 wherein said tarr residue contains at least 15 parts by weight of said 2,3,4,5-bis(A-butehylene)-tetrahydrofurfural.

20. A product of vulcanization of 100 parts by weight of a rubbery butadiene-acrylonitrile copolymer vulcanized with sulfur in the presence of from 1 to 50 parts by weight of a tarry residual by-product containing 2,3,4,5-bis(A -butenylene) -tetrahydrofurfural and recovered from furfural previously utilized as a selective solvent in the extractive distillation of 1,3-butadiene from a C4 hydrocarbon mixture.

21. A vulcanizate of claim 20 wherein said tarry residue contains at least 15 parts by weight of said 2,3,4,5bis(A -butenylene) -tetrahydrofurfural.

22. As a new composition 100 parts by weight of a synthetic sulfur-vulcanizable rubber-like material having a raw Mooney viscosity of at least (ML-4) incorporated with from 15 to 50 parts by weight of an aldehyde characterized by the structural formula where each R is of the group consisting of hydrogen and methyl and at least one is hydrogen,

and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the R'm and in the R'n in each case, not greater than three and at least two of the R'm and of the Rn are hydrogen.

' 23. The composition of claim 22 wherein said aldehyde is 2,3,4,5-bis(A -butenylene) -tetrahydrofurfural and said synthetic elastomer is a rubbery polymer of a conjugated/hydrocarbon diene.

24. As a new composition 100 parts by weight of a synthetic sulfur-vulcanizable rubber-like material having a raw Mooney viscosity of from 40 to 90 (ML-4) incorporated with from 2 to parts by weight of an aldehyde characterized by the structural formula where each R is of the group consisting of hydrogen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the R'm and in the 13/21 in each case, not greater than three and at least two of the R'm and of the vRn are hydrogen.

25. As a new article of manufacture a gasket comprising vulcanized rubbery butadieneacrylonitrile copolymer compounded with an aldehyde characterized by the structural formula where each R is of the group consisting of hydrogen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms With the sum of the carbon atoms in the R'm and in the Rn in each case, not greater than three and at least two of the Rm and of the R'n are hydrogen.

26. As a new article of manufacture a tank, a liner bonded to said tank and a liquid hydrocarbo nfuel contained within said liner, said liner being fabricated from a vulcanized rubbery 'butadiene-acrylonitrile copolymer compounded with an aldehyde characterized by the structural formula i i B'...c I i R/C-RG. l t R'm( J\ /0 3 /C-R,. Rm-C 90 C-R HC=O where each R, is of the group consisting of hydrogen and methyl and at least one is hydrogen, and each R is of the group consisting of hydrogen and an alkyl group having not more than three carbon atoms with the sum of the carbon atoms in the R'm and in the Rn in each case,

not greater than three and at least two of the R'm and of the R'n are hydrogen.

No reference cited. 

26. AS A NEW ARTICLE OF MANUFACTURE A TANK, A LINER BONDED TO SAID TANK AND A LIQUID HYDROCARBON FUEL CONTAINED WITHIN SAID LINER, SAID LINER BEING FABRICATED FROM A VULCANIZED RUBBERY BUTADIENE-ACRYLONITRILE COPOLYMER COMPOUNDED WITH AN ALDEHYDE CHARACTERIZED BY THE STRUCTURAL FORMULA 